Duration of Breast-Feeding Linked to IQ in Adulthood

Babies who are breast-fed longer have higher IQs as young adults, according to findings reported in the Journal of the American Medical Association. In this study, mean IQ scores in adults increased with increasing duration of breast-feeding up until 9 months:

Duration of Breast-Feeding

IQ in Adulthood

<1 month

99.4

2-3 months

101.7

4-6 months

102.3

7-9 months

106.0

>9 months

104.0

The positive effect of breast-feeding on IQ was found even after the study authors adjusted for a wide range of possible confounding factors, such as parental social status and education, single mother status, mother?s age, cigarette consumption during the third trimester, and delivery complications.